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101.
Nonlinear Dynamics - Brand-new equations which can be regarded as modifications of Khokhlov–Zabolotskaya–Kuznetsov or Ostrovsky–Vakhnenko equations are suggested. These equations... 相似文献
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Artem Cherepakha Vladimir O. Kovtunenko Andrey Tolmachev Oleg Lukin 《Journal of heterocyclic chemistry》2013,50(5):1071-1077
A set of synthetic procedures was developed to yield functionalized pyrido‐, pyrimido‐, and thiazo‐annulated thiadiazine‐1,1‐dioxides on a preparative scale. In all cases the thiadiazine‐1,1‐dioxide ring closure was carried out through a reaction of hetaryl‐sulfonyl chlorides with amidines under mild noncatalytic conditions. In the case of 2‐chloropyridine‐3‐sulfonyl chloride derivatives and 2,4‐dichlorothiazole‐5‐sulfonyl chloride open‐chain sulfonylated amidine intermediates were isolated and then subjected to the cyclization step. The reaction with 2,4‐dichloropyrimidine‐5‐sulfonyl chloride gave rise to the corresponding thiadiazine‐1,1‐dioxides in one‐pot. Similarly, a reaction of 2‐chloropyridine‐3‐sulfonamide with lactime ethers proceeded in one‐pot readily giving the corresponding thiadiazine‐1,1‐dioxides. Remaining chlorine atoms on the prepared hetaryl‐annulated benzothiadiazine‐1,1‐dioxides readily undergo aromatic nucleophilic displacement reactions serving thus as additional variation points for the design of biologically potent compounds. 相似文献
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Irina L. Odinets Oleg I. Artyushin Elena V. Sharova Ekaterina V. Matveeva Alexandr N. Turanov Vasilii K. Karandashev 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-3):146-149
Abstract The extraction properties of a series of carbamoylmethylphosphine oxides and β-aminophosphine oxides with lanthanide metal ions is presented. Tris[bis(2-diphenyl- phosphorylethyl)-aminoethyl]amine is shown to be highly effective for extraction of Re(VII). 相似文献
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Oleg I. Kolodiazhnyi Oleg R. Golovatyi 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-4)
Abstract N-Chloroalkylamines react usually with tervalent phosphorus compounds to afford products, containing the phosphorus-nitrogen bond. We found that the sterical hindrances favour to the nucleophilic attack of the tervalent phosphorus atom on the “positive” halogen atom with the formation of phosphorus halogenated products. Sterical hindered N-halogenoalkylamines I (Hlg[dbnd]Cl,Br) possess active halogenating properties to react with tervalent phosphorus compounds similarly to methane tetrahalides. Reaction proceeds via the formation of halogenophosphonium intermediates 2, containing an anion R2N, which reacts with alcohols to afford alkoxyphosphonium salts, transforms into halogenophosphonium salts or P-halogenoylids. Advantages of N-halogenoalkylamines 1 over methane tetrahalides are more high chemical selectivity. Moreover the inclusion of chiral substituents R into N-halogenoalkylamines gives enantioselective halogenating reagents. 相似文献
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